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We present precise lattice computations for the b-quark mass, the quark mass ratios mb/mc and mb/ms as well as the leptonic B-decay constants. We employ gauge configurations with four dynamical quark flavors, up/down, strange and charm, at…

High Energy Physics - Lattice · Physics 2016-06-15 ETM Collaboration , A. Bussone , N. Carrasco , P. Dimopoulos , R. Frezzotti , P. Lami , V. Lubicz , E. Picca , L. Riggio , G. C. Rossi , S. Simula , C. Tarantino

We determine the charm and strange quark masses in the $\overline{\text{MS}}$ scheme, using $n_f=2+1+1$ lattice QCD calculations with highly improved staggered quarks (HISQ) and the RI-SMOM intermediate scheme to connect the bare lattice…

High Energy Physics - Lattice · Physics 2018-08-08 A. T. Lytle , C. T. H. Davies , D. Hatton , G. P. Lepage , C. Sturm

We give some estimates for the light-quark mass dependence of the pole position of the sigma ($f_{0}(500)$) resonance in the complex energy plane, with the help of a chiral Lagrangian for the resonance field and some input from hadronic…

Nuclear Theory · Physics 2016-12-26 Peter C. Bruns

We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass…

High Energy Physics - Lattice · Physics 2019-08-17 C. Alexandrou , A. Borrelli , S. Güsken , F. Jegerlehner , K. Schilling , G. Siegert , R. Sommer

We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form…

We use the ${\cal O}(\alpha_s^3)$ approximation of the heavy-quark vacuum polarization function in the threshold region to determine the bottom quark mass from nonrelativistic $\Upsilon$ sum rules. We find very good stability and…

High Energy Physics - Phenomenology · Physics 2014-05-23 Alexander A. Penin , Nikolai Zerf

We reanalyse the topological susceptibility assuming the possibility of a significant paramagnetic suppression of the three-flavour quark condensate and a correlated enhancement of vacuum fluctuations of $s\bar{s}$ pairs. Using the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Veronique Bernard , Sebastien Descotes-Genon , Guillaume Toucas

We derive rigorous lower bounds for the combinations of light quark masses (m_s+m_u) and (m_d+m_u).

High Energy Physics - Phenomenology · Physics 2011-02-01 Laurent Lellouch

We present a lattice study of fluctuations and correlations among the conserved charges baryon number and strangeness in (2+1)-flavor QCD. The lattice calculations are based on a Taylor expansion of the pressure. Results are presented at…

High Energy Physics - Lattice · Physics 2014-11-20 Christian Schmidt

We summarise recent results for the chiral Random Two-Matrix Theory constructed to describe QCD in the epsilon-regime with imaginary chemical potential. The virtue of this theory is that unquenched Lattice simulations can be used to…

High Energy Physics - Theory · Physics 2008-11-26 G. Akemann

We review recent work by the ALPHA and UKQCD Collaborations where masses and matrix elements were computed in lattice QCD using Schr\"odinger functional boundary conditions and where the strange quark mass was determined in the quenched…

High Energy Physics - Lattice · Physics 2015-06-25 Joyce Garden , Marco Guagnelli , Jochen Heitger , Rainer Sommer , Hartmut Wittig

The top quark mass is one of the most intriguing parameters of the standard model (SM). Its value indicates a Yukawa coupling close to unity, and the resulting strong ties to Higgs physics make the top quark mass a crucial ingredient for…

High Energy Physics - Experiment · Physics 2025-04-10 CMS Collaboration

Using the non-relativistic version of Borel sum rules, combined to the very accurate experimental information on the Charmonium and Upsilon spectra, we rigorously investigate the Euclidean mass of the Charm and Bottom quark. Our analysis is…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Chabab , R. Markazi , E. H. Saidi

We study the strange and non-strange quark mass dependence of the parameters of the f_0(600), kappa(800), rho(770) and K*(892) resonances generated from elastic meson-meson scattering using unitarized one-loop Chiral Perturbation Theory. We…

High Energy Physics - Phenomenology · Physics 2015-05-18 J. Nebreda , J. R. Pelaez

We present a determination of the b-quark mass accurate through O(\alpha_s^2) in perturbation theory and including partial contributions at O(\alpha_s^3). Nonperturbative input comes from the calculation of the Upsilon and B_s energies in…

High Energy Physics - Lattice · Physics 2013-04-29 A. J. Lee , C. J. Monahan , R. R. Horgan , C. T. H. Davies , R. J. Dowdall , J. Koponen

We present a study of baryon ground states and low lying excitations of non-strange and strange baryons. The results are based on seven gauge field ensembles with two dynamical light Chirally Improved (CI) quarks corresponding to pion…

High Energy Physics - Lattice · Physics 2015-06-12 Georg P. Engel , C. B. Lang , Daniel Mohler , Andreas Schaefer

We describe the first lattice determination of the strong coupling constant with 3 flavors of dynamical quarks. The method follows previous analyses in using a perturbative expansion for the plaquette and Upsilon spectroscopy to set the…

High Energy Physics - Lattice · Physics 2015-06-25 C. Davies , A. Gray , M. Alford , E. Follana , J. Hein , P. Lepage , Q. Mason , M. Nobes , J. Shigemit su , H. Trottier , M. Wingate

We present results of a quenched QCD simulation with overlap fermions on a lattice of volume V = 16^3X32 at beta=6.0, which corresponds approximatively to a lattice cutoff of 2 GeV and an extension of 1.4 fm. From the two-point correlation…

High Energy Physics - Lattice · Physics 2015-06-25 L. Giusti , C. Hoelbling , C. Rebbi

We discuss preliminary results from our quenched light hadron mass calculation on a $48^3 \times 64$ lattice at the coupling of $\beta = 6.5$. Staggered quarks with masses of $m_q = 0.01, 0.005, 0.0025$ and $0.00125$ are used.

High Energy Physics - Lattice · Physics 2009-10-28 Seyong Kim , Shigemi Ohta

Effects of heavy sea quarks on the low energy physics are described by an effective theory where the expansion parameter is the inverse quark mass, 1/$M$. At leading order in 1/$M$ (and neglecting light quark masses) the dependence of any…